Re: [CAD_CAM_EDM_DRO] Problems in Timing Belt drive system in 6WD robot

Here's an idea that may solve your
turning issues.

Allow the belts to slip on a tensioner that
loosens when excess torque is felt. This would
be akin to those variable transmissions that
are put on snowmobiles.

As excess torque is applied during the turn,
the two halves of the pulley would widen causing
the belt to go deeper into the pulley, which would
be a smaller diameter and causing the effective
increase in RPMs of the outside tires during the turn.

This could be controlled electronically with electro
magnets or mechanically with properly tensioned
springs opposing each other.

Scott A. Tovey
--------------------------------------------------

--- On Sun, 27/1/13, Jon Elson <elson@...> wrote:

> From: Jon Elson <elson@...>
> Subject: Re: [CAD_CAM_EDM_DRO] Problems in Timing Belt drive system in 6WD robot
> To: CAD_CAM_EDM_DRO@yahoogroups.com
> Date: Sunday, 27 January, 2013, 12:19 AM
> KM6VV wrote:
> > The torque between wheels may not be that bad, the
> thrust against the
> > outside wheels would be at right angles, and not
> transmitted.  The
> > wheels would be able to turn, although still needing to
> "slip" on the
> > surface.
> >   
> Yup, in the ASME mud vehicle, the side slip of the corner
> tires was the
> main problem.
> They used large roller chain to couple all the wheels on
> each side, and
> the chains did
> not jump.  But, it was pretty obvious there was a lot
> of tension on the
> chains also
> when you tried to turn.  The whole vehicle was bound up
> until it
> overloaded the
> gas engine.
>
> The side slip of the corner tires is going to be the next
> problem once
> the jumping
> belts is solved.
>
> Jon
>
>
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